Structure-reactivity relations in electrocatalysis

This chapter concerns electrocatalysis as a sub-division of heterogeneous catalysis dealing with reactions at the electrified interfaces. The aim is to provide an understanding of the concept of structure-activity relations in electrocatalysis. The readers will be able to understand the concept of catalyst active sites and their identification. The chapter is structured in three main sections. Initially, the fundamental principles of electrocatalysis and the basics of electrolyzers and fuel cells are introduced. The concept of active sites and so-called volcano plots are elucidated. In the second section, the structure-activity relations in electrocatalysis are elaborated in detail. The electrocatalytic performance of various surface facets, motifs are described. Further, a method based on scanning tunneling microscopy for the direct experimental identification of active sites is demonstrated. In the third section, the restructuring of different electrocatalyst surfaces during reaction conditions is discussed. In addition, aspects of the stability of nanostructured alloyed metal electrocatalysts and approaches to increase it are elaborated.